#include "bits/stdc++.h"
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

typedef long long ll;

int main() {
    ll N, M, K;
    char op;
    cin >> N >> M >> K >> op;
    vector<ll> A(N), B(M);
    rep(i, M) {
        cin >> B[i];
    }
    rep(i, N) {
        cin >> A[i];
    }
    sort(A.begin(), A.end());
    sort(B.begin(), B.end());
    ll ans = 0;
    rep(i, N) {
        int j;
        if (op == '+') j = lower_bound(B.begin(), B.end(), K - A[i]) - B.begin();
        else j = lower_bound(B.begin(), B.end(), (K + A[i] - 1) / A[i]) - B.begin();
        ans += M - j;
    }
    cout << ans << endl;
}